摘要:
A process for producing high purity silicic acid aqueous solution is disclosed, wherein alkali metals in an alkali silicate solution are removed by ion-exchanging, the resulting solution is treated in an electrochemical process in the present of a strong acid and oxidizing agent to solubilize the remaining non-alkali metal salts, and the non-alkali metals in the water soluble salts are removed by ion-exchanging to obtain the silicic acid aqueous solution.
摘要:
2-Amino-1,3-propanediol compounds of the formula (I) ##STR1## wherein R is an optionally substituted straight- or branched carbon chain, an optionally substituted aryl, an optionally substituted cycloalkyl or the like, and R.sup.2, R.sup.3, R.sup.4 and R.sup.5 are the same or different and each is a hydrogen, an alkyl, an aralkyl, an acyl or an alkoxycarbonyl, pharmaceutically acceptable salts thereof and immunosuppressants comprising these compounds as active ingredients.The 2-amino-1,3-propanediol compounds of the present invention show immunosuppressive action and are useful for suppressing rejection in organ or bone marrow tranplantation, prevention and treatment of autoimmune diseases or as reagents for use in medicinal and pharmaceutical fields.
摘要:
In a color cathode-ray tube, only a foreign matter adhering to a shadow mask is removed effectively without thermal deformation of the shadow mask or thermal denaturation of phosphors.An electron beam produced by an electron gun incorporated in a cathode-ray tube itself is scanned or irradiated to all over a shadow mask of the color cathode-ray tube. The radiant state of a fluorescent screen at this stage is checked to detect a foreign matter adhering to the shadow mask. The electron beam is deflected to align with the position at which the foreign matter is detected, and then irradiated to the foreign matter in the form of pulses. Thus, the foreign matter is heated and removed.
摘要:
An ion implantation apparatus comprises an ion beam measuring device to measure and analyze the shape of a beam projected on a substrate for ion implantation and the quantity of current obtained by the ion beam, an analyzing slit member having an opening whose width is changeable, which is located in the ion beam track to extract only implantation ions, and a shaping slit member having an opening whose width is changeable, which is located behind the analyzing slit member to determine the shape of the beam to be projected on the substrate for ion implantation, wherein the widths of the openings of the analyzing slit member and the shaping slit member are changed on the basis of the shape of the beam and the quantity of current obtained as a result of the measurement by the ion beam measuring device.
摘要:
A push-up pin used for separating a semiconductor element attached by adhesive to an adhesive sheet of a semiconductor element pushing-up device in a die bonding apparatus from the adhesive sheet by pushing up the semiconductor element from the rear surface side of the adhesive sheet includes a tip end portion having a shape for applying pushing-up pressure with the thicknesses of the adhesive sheet and the adhesive kept constant when the pushing-up pressure for pushing up the semiconductor element from the rear surface side of the adhesive sheet is applied, and a base portion for supporting the tip end portion.
摘要:
A push-up pin used for separating a semiconductor element attached by adhesive to an adhesive sheet of a semiconductor element pushing-up device in a die bonding apparatus from the adhesive sheet by pushing up the semiconductor element from the rear surface side of the adhesive sheet includes a tip end portion having a shape for applying pushing-up pressure with the thicknesses of the adhesive sheet and the adhesive kept constant when the pushing-up pressure for pushing up the semiconductor element from the rear surface side of the adhesive sheet is applied, and a base portion for supporting the tip end portion.
摘要:
Grooves are formed in a surface of a wafer, on which surface semiconductor elements are formed, along dicing lines. The grooves are deeper than a thickness of a finished chip. A holding member is attached on the surface of the wafer on which the semiconductor elements are formed. A bottom surface of the wafer is lapped and polished to the thickness of the finished chip, thereby dividing the wafer into chips. When the wafer is divided into the chips, the lapping and polishing is continued until the thickness of the wafer becomes equal to the thickness of the finished chip, even after the wafer has been divided into the chips by the lapping and polishing.
摘要:
An ion implantation apparatus includes an ion source having an arc chamber generating ions and a drawing electrode drawing ions from the arc chamber, a mass separator transporting only ions desired for implantation, an ion implantation chamber in which the material to be implanted by ions is placed, and a controller means for automatically controlling the distance between the arc chamber and the drawing electrode incrementally in accordance with a theoretical calculation using normalized perveance considering the kind of ions to be implanted, the accelerating voltage, and the ion current and current density distribution.
摘要:
In a tape cartridge of the Philips type, one or more ribs are projected from a main plate of each case half at regions except for the tape chamber and the tape path so as to conform to one or more flow lines of resin when each half of molded, the cartridge is so that the formation of traces of resin can be prevented, resulting in an increase in mechanical strength of the cartridge.
摘要:
In a tape cartridge of the type having a front lid for protection of the tape and the position thereof in a tape player is decided by a positioning member of the tape player, a reference face of the tape cartridge to which the positioning member of the tape player abuts is provided on the front end portion of the side wall of the cartridge so as to avoid interference with the front lid and the positioning member and to avoid the need for providing an opening in the front lid for passing the positioning member.